Toxicology of insecticides to mammals

Many insecticides target structures or functions in non-target species, including mammals. This is particularly true of those that target the insect nervous system, such as the organochlorines, anticholinesterases and GABA antagonists. Another group of insecticides target structures or functions not present in mammals, and this group of insecticides has considerable target species specificity, but there are often potential targets in mammals. Octopamine is closely related to adrenaline and amitraz (an octopamine receptor agonist) and acts in mammals at α2-adrenergic receptors. Although there are potential targets in mammals for juvenile hormone mimics and ecdysone receptor agonists, there is no evidence that the mammalian toxicity of either group is related to their insecticidal activity. Nor do chitin synthesis inhibitors have high mammalian toxicity. Copyright © 2012 Society of Chemical Industry     

环境毒理学教学改革的探讨

从教学内容、教学方法(强化课堂教学,采用研究型教学和讨论式或报告式教学)和考核方式3个方面对环境毒理学课程教学的改革进行了探讨,有利于提高教学质量和教学效果,为培养具有较高综合素质的环境科学专业合格人才提供重要保证。     

中国大螟研究历史、现状与展望

为了深入研究大螟发生特点、探索其危害规律,提出合理有效的防治手段,有效防控大螟危害,笔者以近50年来中国的大螟研究为基础,综述了大螟生物学、生态学、为害特点、防治技术、人工饲养技术、抗药性和毒理以及预测预报等方面取得的进展,并提出了未来大螟研究的方向。     

Prospective determination of the specificity of a commercial snake venom detection kit in urine samples from dogs and cats

Objective To determine the specificity of a snake venom detection kit in urine samples from dogs and cats presenting to a referral centre for diseases unrelated to snake envenomation. Design Urine was collected from 50 dog and 25 cats presented for investigation and treatment of diseases unrelated to snake envenomation. Urine was collected as a voided sample, by cystocentesis or by catheterisation, and routine urinanalysis was performed. Snake venom testing was performed within 2 h of collection using a commercially available snake venom detection kit, which was observed continuously during the 10-min colour reaction phase for evidence of a visible colour indicating a positive test. Results No false-positive reactions occurred in any sample analysed. Conclusion The snake venom detection kit appears to have 100% specificity for using urine as a test sample.     

Incidence of prolonged prothrombin time in dogs following gastrointestinal decontamination for acute anticoagulant rodenticide ingestion

Objective: To determine the effect of gastrointestinal (GI) decontamination on the incidence of prolonged prothrombin time (PT) in dogs after anticoagulant rodenticide ingestion. Design: Retrospective study. Setting: Urban emergency room. Animals: One hundred and fifty‐one client‐owned dogs. Measurements: Dogs presented to the emergency room within 6 hours of ingestion of an anticoagulant rodenticide and had a PT measured within 2–6 days of toxicant ingestion before initiating vitamin K therapy were included. Dogs were categorized as treated or untreated based on the institution of vitamin K therapy following PT testing. The signalment, body weight, type of rodenticide ingested, time elapsed between ingestion and initial presentation, method(s) of GI decontamination, and the times elapsed between both toxicant ingestion and initial hospital presentation until determination of PT were recorded. The PT results were recorded as well as any treatment received following the recheck examination. Any reported incidents of bleeding or untoward effects between exposure and reexamination were recorded. Main results: Of 151 dogs, only 11 dogs (8.3%) developed prolonged PT requiring vitamin K supplementation. None of the 11 dogs with prolonged PTs exhibited signs of bleeding or required transfusion therapy. No differences in age, weight, or time elapsed between treated and untreated patients were found. Conclusions: The incidence of prolonged PT is low in dogs receiving GI decontamination within 6 hours of anticoagulant rodenticide ingestion. Delaying vitamin K therapy until a PT has been assessed 48–72 hours after initial exposure appears to be safe and sensitive in dogs following anticoagulant rodenticide ingestion.     

薄盖灵芝菌粉主要成分分析及安全毒理学试验

推荐灵芝科另一种药用真菌———薄盖灵芝 ,其菌粉可视为一种保健食品新资源。分析结果表明 :薄盖灵芝菌粉的水分、粗蛋白、粗脂肪、总醣、粗纤维、还原糖和灰分的含量 ,两倍于灵芝和紫芝子实体含量 ;其十八种氨基酸总量为 10 34～ 10 4 7g/10 0g ;其脂肪酸构成上以油酸 ,亚油酸、亚麻酸等不饱和脂肪酸为主 ;急性及亚急性毒性试验结果表明 :薄盖灵芝菌粉口服安全无毒 ,无致突变作用 (遗传毒性 ) ,对小白鼠的半致死量大于 2 0g/kg ,属实际无毒级 ,对大白鼠的生长发育无不良影响。该菌可参照已知的药理作申报其保健功能。     

An intratracheal instillation bioassay system for detection of lung toxicity due to fine particles in f344 rats

It is an urgent priority to establish in vivo bioassays for detection of hazards related to fine particles, which can be inhaled into deep lung tissue by humans. In order to establish an appropriate bioassay for detection of lung damage after particle inhalation, several experiments were performed in rats using quartz as a typical lung toxic particle. The results of pilot experiments suggest that Days 1 and 28 after intratracheal instillation of 2 mg of fine test particles in vehicle are most appropriate for detection of acute and subacute inflammatory changes, respectively. Furthermore, the BrdU incorporation on Day 1 and the iNOS level on Day 28 proved to be suitable end-point markers for this purpose. An examination of the toxicity of a series of particles was performed with the developed bioassay. Although some materials, including nanoparticles, demonstrated toxicity that was too strong for sensitive assessment, a ranking order could be clarified. The bioassay thus appears suitable for rapid hazard identification with a possible ranking of the toxicity of various particles at single concentrations.